Creeping Oxalis is a creeping summer perennial broadleaf weed that is also commonly known as Creeping Woodsorrel, Oxalis and Sourgrass. Its scientific name is Oxalis corniculata.
Creeping Oxalis can be identified by its numerous branches sprouting from a slender taproot. These branches form slightly hairy stems, which are green to purple in color and root at the nodes. This broadleaf weed also has leaves that are heart-shaped and deeply lobed, growing on long petioles. They are often tinged reddish-purple. Blooming in spring, summer and fall, Creeping Oxalis produces flowers with five yellow petals, forming in clusters of one to five, at the end of its slender stems. Reproduction occurs by seeds and stolons that root at the nodes. Creeping Oxalis can be distinguished from Oxalis by its pronounced horizontal growth habit.
This broadleaf weed frequently grows in lawns and gardens. It is found in much of the continental United States.
Proper cultural practices, such as proper mowing and watering, can help to prevent Oxalis corniculata by creating dense turf, which inhibits the weed's ability to grow. Physical removal (i.e., weed-pulling) can be effective, though you run the risk of spreading the seeds to additional areas of your lawn and landscaping.